Many-body effects on properties of attractive Bose-Einstein condensates.

对有吸引力的玻色-爱因斯坦凝聚体特性的多体效应。

• 批准号: 15340129
• 负责人: UEDA Masahito
• 金额: $ 5.06万
• 依托单位: Tokyo Institute of Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2003
• 资助国家: 日本
• 起止时间: 2003 至 2005
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-15340129/
• 关键词: Atomic and Molecular Physics; Low temperature physics; Condensed matter theory; Bose-Einstein condensates; 引力相互作用; 非線形相互作用; 低次元系; 多体効果; 量子ホール効果

We have studied effects of interactions on properties of gaseous Bose-Einstein condensates (BECs) by focusing on many-body effect and attractive interactions. Below follows the summary of our main results.(1) Fast rotating BEC. We have shown that a rotating BEC makes a quantum phase transition to the Laughlin state when the angular momentum of the system exceeds h N(N-1), where N is the number of atoms. Above the Laughlin state we find a single-particle excitation branch similar to the roton branch. This branch has been found in fractional quantum Hall systems with a long-range Coulomb interaction. Our system has short-ranged and therefore offers a new insight into this gapful mode.(2) A BEC is usually created in a confining potential. It is well known that in dimensions higher than one dimension BEC will either collapse or expand in free space. We have shown that the BEC can be stabilized in 2D free space by oscillating the strength of interactions between attractive and repulsive interactions using a Feshbach resonance.(3) In 3D free space, we have found that BEC cannot be stabilized by the above method, but can be stabilized in the presence of dissipation. This state of matter may be viewed as a self-trapped gaseous superfluid in free space.

本文从多体效应和吸引相互作用两个方面研究了相互作用对气态玻色-爱因斯坦凝聚体性质的影响。下面是我们主要结果的总结。(1)快速旋转BEC。我们证明了当系统的角动量超过hN（N-1）时，旋转BEC发生量子相变，到达Laughlin态，其中N是原子数.在Laughlin态之上，我们发现了一个类似于旋子分支的单粒子激发分支。这个分支已经在具有长程库仑相互作用的分数量子霍尔系统中被发现。我们的系统具有短程性，因此为这种间隙模式提供了新的见解。(2)BEC通常在限制势中产生。众所周知，在高于一维的维度中，BEC在自由空间中要么坍缩要么膨胀。我们已经表明，BEC可以稳定在2D自由空间中振荡的吸引力和排斥力之间的相互作用的强度使用Feshbach共振。(3)在三维自由空间中，我们发现BEC不能用上述方法稳定，但可以在耗散存在的情况下稳定。这种物质状态可以被视为自由空间中的自陷气态超流体。

项目成果

Vortex molecules in coherently coupled two-component Bose-Einstein

相干耦合二元玻色-爱因斯坦中的涡旋分子

• 发表时间: 2004
• 期刊: Physical Review Letters 93
• 作者: K.Kasamatsu;M.Tsubota;M.Ueda
• 通讯作者: M.Ueda

Energy gaps and roton structure above the ν=1/2 Laughlin state of a rotating dilute Bose-Einstein condensate.

旋转稀释玻色-爱因斯坦凝聚体 ν=1/2 劳克林态上方的能隙和旋转结构。

• 发表时间: 2003
• 期刊: Phys.Rev.Lett. 91
• 作者: T.Nakajima;M.Ueda
• 通讯作者: M.Ueda

レーザー冷却された原子気体のボース・アインシュタイン凝縮 (単行本、共著) "現代物理学の歴史と展望"

激光冷却原子气体的玻色-爱因斯坦凝聚（精装，合着）《现代物理学的历史与前景》

• 发表时间: 2004
• 作者: M.Ueda;H.Satio;上田 正仁
• 通讯作者: 上田 正仁

Bose-Einstein droplet in free space

• DOI: 10.1103/physreva.70.053610
• 发表时间: 2004-07
• 期刊: Physical Review A
• 影响因子: 2.9
• 作者: H. Saito;Masahito Ueda

T.Nakajima, M.Ueda: "Energy gaps and roton structure above the Laughlin state of a rotating dilute Bose-Einstein condensate"Phys.Rev.Lett.. vol.91. 140401(1)-140401(4) (2003)

T.Nakajima、M.Ueda：“旋转稀玻色-爱因斯坦凝聚体劳克林态上方的能隙和旋转结构”Phys.Rev.Lett.. vol.91。